Problema Solution
The force needed to keep a car from skidding on a curved roadway using a new, experimental rain tire varies jointly as the weight of the car and the square of the speed of the car and inversely as the radius of the curve. Using these tires, it takes 3000 pounds of force to keep a 2000 pound car from skidding on a curve whose radius is 400 feet at the speed of 50 miles per hour. What force would be required to keep the same car, using the same tires, from skidding on a curve whose radius is 475 feet at a speed of 60 miles per hour.
Answer provided by our tutors
The force needed to keep a car from skidding on a curved roadway using a new, experimental rain tire varies jointly as the weight of the car and the square of the speed of the car and inversely as the radius of the curve. Using these tires, it takes 3000 pounds of force to keep a 2000 pound car from skidding on a curve whose radius is 400 feet at the speed of 50 miles per hour. What force would be required to keep the same car, using the same tires, from skidding on a curve whose radius is 475 feet at a speed of 60 miles per hour.
F =kwv^2/r.
k=Fr/wv^2
.
k=3000*400/(2000*50^2) =0.24.
F=0.24*2000*60^2/475.
=3638 pounds.